Advantages of Electret Microphone | disadvantages of Electret Microphone
This page covers advantages and disadvantages of Electret Microphone and its basics. It mentions benefits or advantages of Electret Microphone and drawbacks or disadvantages of Electret Microphone.
It works on the same principle as condenser microphone. The condenser microphone consists of two thin plates which form a capacitor. One plate is flexible and the other is rigid. In this microphone type, equal and opposite charge is being applied to the plates. When pressure is applied, capacitance between them varies accordingly. If charge on plates is kept constant when capacitance fluctuates, voltage across it fluctuates.
What is Electret Microphone?
It works on the same principle as condenser microphone. Its plates are made of ferroelectric material. Hence it retains electric charge similar to iron which retains magnetic polarization. Electrets are used in laptop and portable phones. It consists of about 90% of microphones in use today.
The figure depicts basic circuit of electret microphone. It generates very small amount of current and hence transistor or operational amplifier is required to boost the signal. The term "Electret" has been derived from "Electrostatic" and "magnet". This microphones are available with leads attached and with solder pads for surface mount applications.
Benefits or advantages of Electret Microphone
Following are the benefits or advantages of Electret Microphone:
➨They are inexpensive microphone type.
➨Recent electret microphones are providing good quality compare to condenser microphones.
➨They are suitable for extremely wide frequency response.
➨They are best for voice recording for interviews.
➨It eliminates need for polarizing power supply by using permanently charged material.
Drawbacks or disadvantages of Electret Microphone
Following are the drawbacks or disadvantages of Electret Microphone:
➨It requires external components such as transistor or op-amp to boost the small amount of current signal created by it. Usually these components are integrated on the same chip.
➨They are less sturdy compare to dynamic microphones.
➨Vibrating membrane may wear out in a couple of years.
➨More fragile overall compare to dynamic microphone.
➨The cheap versions of this microphones offer poor quality. Moreover they offer low sensitivity.
➨Some users find bass range unsatisfactory.